Container-filling machine with level sensing and blowdown

Abstract

A level-sensing collar is rigidly mounted on a vertical tubular nozzle of a container-filling machine. The collar is located a predetermined distance above the nozzle outlet and is provided in its bottom with an upwardly extending recess encircling the nozzle. The collar also has a plurality of circumferentially spaced openings connecting its recess with the lower ends of air tubes that extend up along the nozzle to air-receiving means that first receives high pressure air to blow down out of the collar recess any product that has accumulated in it and then receives low pressure air for delivery to the collar recess so that when the level of the product in a surrounding container rises high enough to close the recess the air pressure in the tubes will built up and shut off the delivery of the product to the container.

I claim: 
     
       1. In a container-filling machine, the combination with a vertical tubular nozzle provided at its lower end with an outlet for discharging a semi-liquid product into a surrounding container, of a level-sensing collar rigidly mounted on the nozzle in sealing engagement therewith and provided in its bottom with an upwardly extending recess encircling the nozzle, the collar being spaced above the nozzle outlet and having a plurality of circumferentially spaced openings extending downwardly through it into said recess, air tubes connected to the upper ends of said openings and extending upwardly therefrom along the nozzle, air-receiving means connected with the upper ends of said tubes, means for supplying high pressure air to said air-receiving means for the tubes to deliver to said collar recess to blow down out of it any of said product that has accumulated in it, and means for then supplying low pressure air to said air-receiving means for the tubes to deliver to said collar recess. 
     
     
       2. In a container-filling machine according to claim 1, there being three of said collar openings and three of said tubes. 
     
     
       3. In a container-filling machine according to claim 1, said air-receiving means including a ring encircling the upper end of said nozzle and rigidly secured thereto, the ring being provided with an interior recess encircling the nozzle, the bottom of the ring having circumferentially spaced openings therein connecting the upper ends of said tubes with said ring recess, and said ring having a further opening communicating with its recess and forming an inlet for said air. 
     
     
       4. In a container-filling machine according to claim 3, there being three of said collar openings and three of said tubes and three of said tube-receiving openings in said ring. 
     
     
       5. In a container-filling machine according to claim 1, a tube connected with said air-receiving means, said air-supplying means including a valve provided with an outlet connected with said tube and having two inlets, means for conducting high pressure air to one of said inlets, means for conducting low pressure air to the other valve inlet, and means in said valve for first connecting said high pressure air and then said low pressure air with said valve outlet.